Wednesday, September 14, 2005

Been a very busy month

I have IPS (see IPS ) running on the AMSAT IHU-3. The IHU is the internal housekeeping unit of the spacecraft. It receives and processes commands, it maintains the state of the spacecraft and attempts to mitigate faults and generally manage the health of the spacecraft. I have pictures of our meetings in Germany and Washington state in these gallery entries:

We can talk to the bus of the spacecraft and programming of the IHU flight code has commenced.

The American Radio Relay League sponsors technical working groups. I am chairperson for the Software Defined Radio working group and a member of the High-Speed Digital Networks and Multimedia Working Group. We are working on a class of modems ideally suited for both HF and VHF and Microwave communications. The modem class is called OFDM and this is orthogonal frequency division multiplexing. This is a fancy name for sending a bunch of data down parallel channels (parallel in frequency) and done in a way that the frequencies used provide an very nice mathematical property which aids considerably in the modulation and demodulation of these signals.

AMSAT will be holding a board of directors meeting and AMSAT Eagle spacecraft design meeting in Pittsburgh Oct. 6-9. I will be demonstrating with my partners a working software defined transponder SDX. You can hear the first QSO by visiting

By the time of my next entry, I will know if I am on the board of directors of AMSAT. I was talked into it, I have done it before and chose not to run back when AEA failed and amateur radio lost its luster. I am glad it has regained it.